The Empire of Opposition, also referred by humans as the Empire of Unfriendly Beings, Empire of Darkness, and Empire of Evil, was one of the two alien-only organizations formed in 1000 BBY a few months after the end of the New Sith Wars. Unlike the Remnant, the Opposition rose to power during the aftermath of the Battle of Zerah where the Jedi defeated the Sith, and unintentionally, also killing the planet.
The Opposition operated alongside the Remnant to punish and destroy all humans in the galaxy for Zerah. Many Jedi and Sith-allied aliens joined the Opposition as well as aliens who were former Jedi and Sith who continued to use their respective power of the Force and became known as the Opposition Founding Fathers whereas regular, non Force-sensitive aliens were either placed in the Opposition Army, Navy, or the Volunteer Forces. Other oversized aliens who were over ten feet tall were considered as Behemoths and placed into the Opposition Behemoths of War, the same applied to the Remnant Military as well.